Cooling device, and electronic apparatus with the cooling device

ABSTRACT

According to one embodiment, a cooling device is provided with a heat receiving member connected to a heat generator, a heat pipe connected to the heat receiving member, a heat dissipation fin connected to the heat pipe at an opposite side of the heat receiving member, and a fan configured to cool the heat dissipation fin. The cooling device is also provided with a tank containing a liquid and thermally connected to the heat receiving member.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2012-262294, filed Nov. 30, 2012, the entire contents of which are incorporated herein by reference.

FIELD

Embodiments described herein relate generally to cooling devices using heat pipes, and electronic apparatuses with the cooling devices.

BACKGROUND

Some portable electronic apparatuses, such as note PCs, are provided with a cooling device for cooling a heat emitting component, such as a CPU. It is known that cooling devices of this type include those using a heat pipe. The heat pipe has one end thereof thermally connected to a heat generation component, and the other end thereof thermally connected to a heat dissipation component, such as a fin. The liquid in the heat pipe receives heat from the heat generation component to be evaporated at the one end of the pipe, and the resultant gas is cooled to be re-liquidized at the other end. The liquid obtained at the other end is returned to the one end. Thus, circulation is performed in the heat pipe.

When such a heat pipe as the above is used, if an electronic device is constructed such that its heat generation component is at a vertically higher position than its heat dissipation component (i.e., if the electronic device is in a top heat state), it is difficult to upwardly move a liquidized coolant to the heat generation component against the gravity. A cooling device, which has been developed in light of this to include two heat pipes extending from a heat generation component in different directions, is known.

Although this cooling device exhibits enhanced cooling performance, it is too large and too heavy.

Under the above circumstances, there is a demand for development of a small and light cooling device that can exert constant cooling performance regardless of the condition of use, and for an electronic device with such a cooling device.

BRIEF DESCRIPTION OF THE DRAWINGS

A general architecture that implements the various features of the embodiments will now be described with reference to the drawings. The drawings and the associated descriptions are provided to illustrate the embodiments and not to limit the scope of the invention.

FIG. 1 is a perspective view illustrating a tablet PC as an example of electronic equipment with a cooling device according to a first embodiment;

FIG. 2 is a perspective view illustrating the tablet PC of FIG. 1 when viewed from behind;

FIG. 3 is a schematic view illustrating the internal structure of the tablet PC of FIG. 2 viewed when its backside housing is removed;

FIG. 4 is a schematic enlarged view illustrating the cooling device of the first embodiment incorporated in the tablet PC of FIG. 3;

FIG. 5 is a cross sectional view taken along line F5-F5 of FIG. 4;

FIG. 6 is a schematic view useful in explaining the function of the cooling device assumed when the tablet PC of FIG. 1 is used in a landscape mode;

FIG. 7 is a schematic view useful in explaining the function of the cooling device assumed when the tablet PC of FIG. 6 is used in a portrait mode;

FIG. 8 is a schematic view illustrating a cooling device according to a second embodiment;

FIG. 9 is a schematic view illustrating a state in which a tablet PC equipped with the cooling device of FIG. 8 is used in the landscape mode;

FIG. 10 is a schematic view illustrating a state in which the tablet PC of FIG. 9 is used in the landscape mode;

FIG. 11 is a schematic view illustrating a cooling device according to a third embodiment;

FIG. 12 is a cross sectional view taken along line F12-F12 of FIG. 11; and

FIG. 13 is an enlarged cross sectional view illustrating the essential part of FIG. 12.

DETAILED DESCRIPTION

Various embodiments will be described hereinafter with reference to the accompanying drawings.

In general, according to one embodiment, a cooling device is provided with a heat receiving member connected to a heat generator; a heat pipe connected to the heat receiving member; a heat dissipation fin connected to the heat pipe at an opposite side of the heat receiving member; and a fan configured to cool the heat dissipation fin. The cooling device is also provided with a tank containing a liquid and thermally connected to the heat receiving member.

FIG. 1 is a perspective view illustrating a tablet PC 100 as an example of an electronic device. FIG. 2 is a perspective view of the tablet PC 100 viewed from behind. FIG. 3 is a schematic view illustrating a state in which a housing 102 at the backside of the tablet PC 100 is removed therefrom.

The tablet PC 100 comprises a display unit 105 that is located at its front side and is provided with a touch panel 106 through which an input operation using a touch pen 104 is possible. The touch pen 104 is provided so that it can be housed in the housing of the tablet PC 100.

The tablet PC 100 further comprises a circuit board 108, a battery 110, a camera module 111, a loudspeaker 112, a memory device 114, a cooling device 10, etc., as shown in FIG. 3. Further, an SD card slot 121, a USB terminal 122, a mini USB terminal 123, an earphone jack 124, etc., are provided in a side surface of the tablet PC 100.

As shown in FIG. 2, in the housing 102 at the backside, there are provided a hole for exposing a camera 111 a incorporated in a camera module 111, and exhaust ports 103 for the cooling device 10. The cooling device 10 is provided at a position inwardly opposing the exhaust ports 103.

FIG. 4 is an enlarged view illustrating the cooling device 10 of the first embodiment. For facilitating the description, a state in which part of the wall is removed is shown so that the interior of a tank 1 can be seen. FIG. 5 is a cross sectional view of the cooling device 10, taken along line F5-F5 of FIG. 4.

As shown, the cooling device 10 comprises a heat receiving plate 2 (heat receiving member) attached to the circuit board 108, directly urged against the surface of a heat generator 5 (see FIG. 5), such as a CPU, mounted on the circuit board 108. The heat receiving plate 2 is formed substantially rectangular, and attachment leg portions 2 a and 2 b as plate springs are integrally extended from the portions of the heat receiving plate 2 near a pair of opposing corners thereof. The attachment leg portions 2 a and 2 b are elastically deformed and have their distal ends screwed to the circuit board 108, thereby exerting a pressing force on the heat generator 5.

On the surface of the heat receiving plate 2 away from the heat generator 5 is thermally connected to one end 4 a of a heat pipe 4. In the first embodiment, the heat pipe 4 is fixed to the heat receiving plate 2 by solder excellent in heat conductance. As shown in the cross section of FIG. 5, the heat pipe 4 has a flat tubular structure, and is angled in an L-shape along the circuit board 108.

The heat pipe 4 contains water and the interior of the heat pipe is kept under negative pressure. The interior of the heat pipe 4 may contain a thin line or a wick for moving the liquid toward the one end 4 a utilizing capillary phenomenon. If the heat pipe 4 is much thinned, the wick or thin line cannot be contained in the pipe. However, the wick is not indispensable element for the invention. The invention is also applicable to a cooling device using a heat pipe that is too thin to contain the wick.

A heat dissipation fin unit 6 is thermally connected to the other end 4 b of the heat pipe 4. The heat dissipation fin unit 6 has a structure in which a plurality of plate-like fins are stacked with gaps defined therebetween. The heat dissipation fin unit 6 opposes the above-mentioned exhaust ports 103 of the housing 102. More specifically, the gaps of the plate-like fins oppose openings of the exhaust ports 103. In other words, the heat pipe 4 is angled in an L-shape to enable the heat dissipation fin unit 6 to oppose the exhaust ports 103.

A fan 8 that blows wind for cooling the heat dissipation fin unit 6 is attached to the opposite side of the heat dissipation fin unit 6 with respect to the exhaust ports 103. Namely, the wind of the fan 8 is exhausted through the exhaust ports 103 after passing through the plate-like fins of the heat dissipation fin unit 6. At this time, the fins of the heat dissipation fin unit 6 are cooled by the wind. A suction port 8 a is formed through the fan 8 from the front side to the rear side thereof.

A tank 1 containing a liquid L (water in the first embodiment) is thermally connected to the surface of the heat receiving plate 2. In the first embodiment, the tank 1 is fixed to the heat receiving plate 2 using solder of a high heat conductivity. The interior of the tank 1 is kept under atmospheric pressure, and the liquid L occupies substantially half the volume of the tank 1. A detailed description will be given later of the appropriate liquid intake capacity of the tank 1.

As shown in the cross sectional view of FIG. 5, the tank 1 also has a flat shape, whereby the whole cooling device 10 is made thin. In the embodiment, in order to make the cooling device 10 as thin as possible, the thickness of the tank 1 is designed to be equal to that of the heat pipe 4. It is sufficient if the thickness of the tank 1 is at least equal to or less than that of the heat pipe 4.

Further, to enhance the thermal transmission efficiency of the cooling device 10, the tank 1, the heat receiving plate 2 and the heat pipe 4 are formed of cooper that has a high heat transmission efficiency. Further, in the embodiment, the tank 1 is fixed to the heat receiving plate 2, after it is positioned so that the heat receiving plate 2 can be made in contact with the tank 1 with as a large area as possible.

Referring mainly to FIGS. 6 and 7, the functions of the above-described cooling device 10 and tank 1 will now be described.

The tablet PC 100 of the first embodiment is mainly used in the landscape mode, i.e., it is mainly operated in the attitude shown in FIG. 1 (in which the camera 111 a is positioned at the top). However, there is a case where the tablet PC 100 is used in the portrait mode (not shown), i.e., it is operated in the attitude in which the SD card slot 121 and the USB terminal 122 are positioned at the top. Further, there is a case where the tablet PC 100, which is portable, is carried with its power kept ON. Therefore, the tablet PC 100 can assume, during use, various attitudes other than the above-mentioned ones.

When the tablet PC is used in the landscape mode that is assumed most frequently, the cooling device 10 assumes the attitude shown in FIG. 6. Namely, in the landscape mode, the cooling device 10 is positioned such that the end 4 b of the heat pipe 4 connected to the heat dissipation fin unit 6 is positioned higher than the end 4 a of the heat pipe 4 connected to the heat receiving plate 2. This attitude is the basic attitude of the cooling device 10 of the embodiment.

In this state, the heat of the heat generator 5 is transmitted to one end 4 a of the heat pipe 4 via the heat receiving plate 2 to thereby heat the liquid in the heat pipe 4. The gas resulting from evaporation of the liquid by the heat passes through the heat pipe 4 to the other end 4 b, where it is cooled and re-liquidized by the heat dissipation fin unit 6. The resultant liquid flows downward through the heat pipe 4 due to gravity and returns to the end 4 a of the heat pipe 4. Thus, in accordance with transmission of heat, coolant of a liquid phase or gas phase circulates in the heat pipe 4, thereby effectively cooling the heat generator 5.

In this state, the liquid L in the tank 1 attached to the heat receiving plate 2 pools in the lower portion of the tank 1 as shown in the enlarged view of FIG. 4, such that the liquid surface is positioned lower than the heat receiving plate 2. Namely, in this state, the liquid L in the tank 1 does not overlap with the heat receiving plate 2. Accordingly, the heat of the heat receiving plate 2 is little transmitted to the liquid L in the tank 1, and almost all heat of the heat receiving plate 2 is transmitted via the heat pipe 4 to the heat dissipation fin unit 6, and is effectively dissipated by the heat dissipation fin unit 6. In other words, when the cooling device 10 is in the attitude shown in FIG. 6 in which it functions most effectively, it is desirable that the heat of the heat receiving plate 2 is transmitted as much as possible to the heat dissipation fin unit 6 so as not to heat the liquid L in the tank 1 as much as possible.

In contrast, when the tablet PC 100 is set in the inverted landscape mode shown in FIG. 7 in which it is positioned upside down, the cooling device 10 is also positioned upside down. This state is a top heat state in which the end 4 a of the heat pipe 4 connected to the heat receiving plate 2 is positioned gravitationally above the other end 4 b of the heat pipe 4 connected to the heat dissipation fin unit 6.

If the tablet PC 100 is used in this state, it is difficult for the liquid, which results from cooling by the heat dissipation fin unit 6 at the other end 4 b of the heat pipe 4, to upwardly flow in the heat pipe 4 against the gravity. In particular, if the cooling device 10 is made too thin to encapsulate, for example, a wick in the heat pipe 4, little liquid moves to the end 4 a of the heat pipe 4, whereby the heat pipe 4 will easily assume a dry-out state. If this state is not eliminated, the capacity of the cooling device 10 for cooling the heat generator 5 may significantly reduce.

In the first embodiment, in such a inversed landscape mode as the above, the liquid L in the tank 1 attached to the heat receiving plate 2 moves and overlaps with the heat receiving plate 2 (i.e., the liquid surface becomes higher than the upper end of the heat receiving plate 2), with the result that part of the heat of the heat receiving plate 2 is transmitted to the liquid L. The heat transmission continues until the temperature of the liquid L is saturated. In other words, in the first embodiment, the amount of the liquid L in the tank 1, the attachment position of the tank 1 with respect to the heat receiving plate 2, etc., are set so that the liquid L can overlap with the heat receiving plate 2 with as a large area as possible at least in the top heat state. It is further preferable that the amount of the liquid L in the tank 1 should be set such that the liquid L in the tank 1 does not overlap with the heat receiving plate 2 when the cooling device 10 assumes the attitude shown in FIG. 6, as is mentioned above.

Namely, in the first embodiment, by attaching the tank 1 to the heat receiving plate 2, reduction of the cooling function of the cooling device 10 can be retarded in the top heat state (shown in FIG. 7), while the function of the cooling device 10 in the standard state of use (shown in FIG. 6) is maintained. Thus, constant cooling performance can be secured regardless of the attitude of the cooling device 10, thereby improving the cooling efficiency. Further, this enables suppression of an increase in the temperature of the housing or the rotational speed of the fan due to abrupt performance degradation in the top heat state, thereby suppressing performance degradation of the heat generator 5 and suppressing the noise occurring during driving the fan.

Since in the first embodiment, the tank 1 is attached closer to the suction port 8 a of the fan 8 than to the heat pipe 4, the liquid L in the tank 1 can also be cooled, which can relatively increase the period of suppression effect of the performance reduction at the top heat time.

Also, since the first embodiment employs a structure in which the tank 1 containing the liquid L is attached to the heat receiving plate 2, the whole device can be prevented from being increased in size and from being significantly increased in weight, whereby the whole device can be manufactured at relatively low cost.

If the liquid L in the tank 1 is water, and a copper body having a high heat conductivity is attached to the heat receiving plate 2 in place of the tank 1, the volume of copper having the same heat capacity as the tank 1 will be ten times or more the volume of the tank 1, since the specific heat of water is 4.2 J/gK and that of copper is 0.379 J/gK. In this case, since weight percent of water is 0.99 and that of copper is 8.82, if the copper body is attached instead of tank 1, the resultant weight will be about 8 times heavier than in the case where the tank 1 is attached. Namely, by employing the apparatus structure of the embodiment where the tank 1 containing the liquid L is attached to the heat receiving plate 2, the cooling device 10 can be made small and light.

Referring then to FIGS. 8 to 10, a cooling device 20 according to a second embodiment will be described. The cooling device 20 has a structure similar to that of the cooling device 10 of the first embodiment except that the former has a heat receiving plate 21 different in size from the heat receiving plate of the first embodiment and the relationship between the heat receiving plate 21 and the tank 1 differs from that in the first embodiment. In the second embodiment, reference numerals corresponding to those of the first embodiment denote similar structural elements, and no detailed descriptions will be given thereof.

As shown in FIG. 8, the cooling device 20 has a heat receiving plate 21 having a smaller in area than the heat receiving plate 2 of the first embodiment. Namely, the heat receiving plate 21 has a size with which the heat receiving plate 21 overlaps with only the upper left portion of the tank 1 in FIG. 8. It is needless to say that the heat receiving plate 21 completely covers the heat generator 5 (not shown). Further, in the second embodiment, the tank 1 is located farther from the fan than the heat pipe 4.

When a tablet PC 100 provided with the cooling device 20 is used in a landscape mode in which the tablet PC assumes the attitude shown in FIG. 9, the liquid L in the tank 1 of the cooling device 20 pools in the lower portion of the tank 1, and the liquid surface is positioned lower than the heat receiving plate 21, i.e., the liquid L in the tank 1 does not overlap with the heat receiving plate 2. In this state, since the end 4 b of the heat pipe 4 connected to the heat dissipation fin unit 6 is positioned gravitationally above the end 4 a of the heat pipe 4 connected to the heat receiving plate 21, the greater part of the heat of the heat generator 5 is transmitted to the heat dissipation fin unit 6, with the result that the heat generator 5 is effectively dissipated by the heat dissipation fin unit 6.

In contrast, when the tablet PC 100 of the attitude shown in FIG. 9 is used in an inverted landscape mode (not shown) in which it is positioned upside down, the liquid L in the tank 1 overlaps with the heat receiving plate 21, as in the first embodiment. Since this state is a top heat state in which the end 4 a of the heat pipe 4 connected to the heat receiving plate 21 is positioned gravitationally above the other end 4 b of the heat pipe 4 connected to the heat dissipation fin unit 6, the heat of the heat receiving plate 21 is transmitted to the liquid L in the tank 1 to thereby suppress reduction of cooling performance.

Further, when the tablet PC with the cooling device 20 is used in the portrait mode shown in FIG. 10, the liquid L pools in the lower portion of the tank 1, and the liquid surface is positioned lower than the heat receiving plate 21, i.e., the liquid L does not overlap with the heat receiving plate 21. Namely, in this state, since the end 4 b of the heat pipe 4 connected to the heat dissipation fin unit 6 is positioned gravitationally above the end 4 a of the heat pipe 4 connected to the heat receiving plate 21, the greater part of the heat of the heat generator 5 is transmitted to the heat dissipation fin unit 6, and the heat generator 5 is effectively dissipated by the heat dissipation fin unit 6.

In contrast, when the tablet PC 100 of the attitude shown in FIG. 10 is used in an inverted portrait mode (not shown) in which it is positioned upside down, the liquid L in the tank 1 overlaps with the heat receiving plate 21, as in the aforementioned inverted landscape mode. Since this state is a top heat state in which the end 4 a of the heat pipe 4 connected to the heat receiving plate 21 is positioned gravitationally above the other end 4 b of the heat pipe 4 connected to the heat dissipation fin unit 6, the heat of the heat receiving plate 21 is transmitted to the liquid L in the tank 1 to thereby suppress reduction of cooling performance.

In other words, the tank 1 is attached to the heat receiving plate 21, such that when the portion (first portion) of the heat pipe 4 between the end 4 a connected to the heat receiving plate 21 and the angled portion 4 c of the (L-shaped) heat pipe 4 is positioned vertically, and the end 4 b of the heat pipe 4 connected to the heat dissipation fin unit 6 is positioned gravitationally above the end 4 a (i.e., when the cooling device is in the attitude shown in FIG. 9), and when the portion (second portion) of the heat pipe 4 between the end 4 b and the angled portion 4 c is positioned vertically, and the end 4 b is positioned gravitationally above the end 4 a (i.e., when the cooling device is in the attitude shown in FIG. 10), the liquid L in the tank 1 does not overlap with the heat receiving plate 21.

Namely, in the second embodiment, when the tablet PC is used in the landscape mode shown in FIG. 9 and in the portrait mode shown in FIG. 10, the greater part of the heat of the heat generator 5 is transmitted to the heat dissipation fin unit 6 to thereby effectively dissipate the heat generator 5, while in the top heat state (not shown), the heat of the heat receiving plate 21 can be transmitted to the liquid L in the tank 1 to thereby suppress reduction of the cooling performance.

Referring then to FIGS. 11 to 13, a cooling device 30 according to a third embodiment will be described. The cooling device 30 has substantially the same structure as the cooling device 10 of the first embodiment except that the tank 1 is attached to the backside of a heat receiving plate 31. In the third embodiment, reference numerals corresponding to those of the first embodiment denote similar structural elements, and no detailed descriptions will be given thereof.

The heat receiving plate 31 of the cooling device 30 is slightly longer than the heat receiving plate 2 of the first embodiment. Namely, in order to arrange the tank 1 on the backside of the heat receiving plate 31 kept in contact with the heat generator 5, the heat receiving plate 31 is elongated along the heat generator 5 and the tank 1 that are located in line.

When the tablet PC 100 with the cooling device 30 is used, placed on, for example, a desk with the touch panel 105 directed upward, the liquid L in the tank 1 of the cooling device 30 pools in the lower portion of the tank and is away from the heat receiving plate 31 as shown in FIG. 13. In this state, the heat of the heat receiving plate 31 is not easily transmitted to the liquid L.

Also when the tablet PC 100 with the cooling device 30 is used in the landscape mode (shown in FIG. 6) as in the first embodiment, the liquid L in the tank 1 does not overlap with the heat receiving plate 31 as in the first embodiment, with the result that the greater part of the heat of the heat generator 5 can be effectively transmitted to the tank 1 via the heat pipe 4.

Further, when the tablet PC 100 with the cooling device 30 is used in such an inverted landscape mode as shown in FIG. 7, and the liquid L in the tank 1 pools in the lower portion of the tank 1 such that the liquid surface is positioned gravitationally above the heat receiving plate 31. As a result, the liquid L overlaps with the heat receiving plate 31. Since this state is a top heat state in which the end 4 a of the heat pipe 4 connected to the heat receiving plate 31 is positioned gravitationally above the other end 4 b of the heat pipe 4 connected to the heat dissipation fin unit 6, the heat of the heat receiving plate 31 is transmitted to the liquid L in the tank 1 to thereby suppress reduction of cooling performance.

Thus, the cooling device 30 of the third embodiment can provide the same advantage as the cooling device 10 of the first embodiment, and the liquid L in the tank 1 can be prevented from being heated when, for example, the tablet PC is used, placed on a desk.

In the cooling device according to at least one of the above-described embodiments, since the tank 1 containing the liquid L is kept in thermal contact with a heat receiving plate connected to a heat generator, the cooling device can have a constant cooling performance regardless of the attitude (state of use) of an electronic device with the cooling device.

While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Indeed, the novel embodiments described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the embodiments described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions.

For instance, although in the above-described embodiments, the invention is applied to the cooling device of a tablet PC as an example of an electronic apparatus, it may also be applicable to another type of electronic apparatus, such as a note PC and a cellular phone. 

What is claimed is:
 1. A cooling device comprising: a heat receiving member connected to a heat generator; a heat pipe connected to the heat receiving member; a heat dissipation fin connected to the heat pipe at an opposite side of the heat receiving member; a fan configured to cool the heat dissipation fin; and a tank containing a liquid and thermally connected to the heat receiving member.
 2. The cooling device of claim 1, wherein when an end of the heat pipe connected to the heat receiving member is positioned gravitationally above another end of the heat pipe connected to the heat dissipation fin, the liquid in the tank overlaps with the heat receiving member.
 3. The cooling device of claim 2, wherein when the end of the heat pipe connected to the heat receiving member is positioned gravitationally below the another end of the heat pipe connected to the heat dissipation fin, the liquid in the tank does not overlap with the heat receiving member.
 4. The cooling device of claim 1, wherein the tank is located closer to a suction port of the fan than the heat pipe.
 5. The cooling device of claim 1, wherein the heat pipe is angled in an L shape; and the tank is attached to the heat receiving member in a positional relationship in which the liquid in the tank does not overlap with the heat receiving member when a first portion of the heat pipe between the end of the heat pipe and an angled portion of the heat pipe extends vertically and the another end of the heat pipe connected to the fin is positioned gravitationally above the end of the heat pipe, and when a second portion between the angled portion of the heat pipe and the another end of the heat pipe extends vertically and the another end of the heat pipe is positioned gravitationally above the end of the heat pipe.
 6. The cooling device of claim 1, wherein the tank is attached to the heat receiving member by solder.
 7. An electronic apparatus comprising: a housing with an exhaust port; a heat generator in the housing; and a cooling device attached to the heat generator, wherein the cooling device comprises: a heat receiving member connected to the heat generator; a heat pipe connected to the heat receiving member; a heat dissipation fin connected to the heat pipe at an opposite side of the heat receiving member, and opposing an inside of the exhaust port; a fan located near the exhaust port with the heat dissipation fin interposed therebetween, and configured to cool the heat dissipation fin; and a tank containing a liquid and thermally connected to the heat receiving member.
 8. The electronic apparatus of claim 7, wherein when the housing assumes an attitude in which an end of the heat pipe connected to the heat receiving member is positioned gravitationally above another end of the heat pipe connected to the heat dissipation fin, the liquid in the tank overlaps with the heat receiving member.
 9. The electronic apparatus of claim 7, wherein when the housing assumes an attitude in which the end of the heat pipe connected to the heat receiving member is positioned gravitationally below the another end of the heat pipe connected to the heat dissipation fin, the liquid in the tank does not overlap with the heat receiving member.
 10. The electronic apparatus of claim 7, wherein the tank is located closer to a suction port of the fan than the heat pipe.
 11. The electronic apparatus of claim 7, wherein the heat pipe is angled in an L shape; and the tank is attached to the heat receiving member in a positional relationship in which the liquid in the tank does not overlap with the heat receiving member when a first portion of the heat pipe between the end of the heat pipe and an angled portion of the heat pipe extends vertically and the another end of the heat pipe connected to the fin is positioned gravitationally above the end of the heat pipe, and when a second portion between the angled portion of the heat pipe and the another end of the heat pipe extends vertically and the another end of the heat pipe is positioned gravitationally above the end of the heat pipe.
 12. The electronic apparatus of claim 7, wherein the tank is attached to the heat receiving member by solder. 